SALT LAKE CITY – SALT LAKE CITY (AP) — Emergency workers believe they have stopped a 21,000 gallon oil leak from reaching the environmentally sensitive Great Salt Lake, one of the West's most important inland water bodies for migratory birds that use it as a place to rest, eat and breed.

An underground pipeline in the mountains near the University of Utah broke Friday night, sending oil into a creek that flows through neighborhoods, into a popular Salt Lake City park and ultimately the Jordan River. The pipeline wasn't shut off until Saturday morning.

Spokesman Jason Olsen said Sunday that emergency workers believe they have contained the spill in the Jordan River, which flows into the Great Salt Lake.

But the spill still took its toll on birds on Red Butte Creek and a pond at Liberty Park. More than 100 birds were coated in oil, and a few have died, Olsen said.

Most of the birds were Canada geese, although some ducks were also covered.

Most of Liberty Park reopened on Sunday. The pond remained closed and Olsen urged those who live near affected waterways to stay away from them.

"Wherever the oil is the smell is still fairly strong," Olsen said.

U.S. Rep. Jim Matheson, D-Utah, said he spoke by telephone with the president of Chevron Pipe Line Company Becky Roberts on Sunday.

Matheson said Roberts told him that until company officials dig up the broken section of pipe, the company can't be sure what caused the leak.

Matheson is urging full disclosure on the cause and said his office would follow up to make sure Chevron follows Environmental Protection Agency regulations.